The invention relates to a control unit for operating a motor vehicle having a plurality of actuators.
Because of low CO2 emissions, there is considerably increasing interest in battery-operated vehicles, particularly in vehicles having a hybrid drive. Vehicles with a hybrid drive structure have an internal-combustion engine and preferably at least one electric machine as the drive assembly. The drive torque during the driving operation of the hybrid vehicle can therefore be generated by both drive assemblies. For this purpose, an energy management system in the vehicle evaluates data of an engine and chassis control as well as of sensors of the driver assistance systems. Depending on the demand, an activation of the electric machine and/or of the internal-combustion engine may take place in a consumption-optimized, power-optimized or emissions-optimized manner. Even in the case of vehicles which only have an internal-combustion engine as a drive assembly, the significance of the energy management system in the motor vehicle is increasing because of a rising multitude of electric consuming devices and an associated increased power consumption.
It is an object of the invention to provide a control unit for operating a motor vehicle, which control unit contributes to the fact that the vehicle can be reliably operated and to the fact that an energy management in the motor vehicle can be simplified and improved.
This and other objects are achieved by a control unit for operating a motor vehicle having a plurality of actuators. The control unit comprises a basic module and a function module, which is constructed in a secured run-time environment. Furthermore, the control unit comprises a specified first and a second interface which each couple the basic module and the function module. The basic module is designed for determining one or more function input quantities, depending on at least one operating quantity, and for making the function input quantities available at the first interface. In addition, the basic module is designed for determining control variables of the actuators, depending on one or more output quantities made available at the second interface. The function module is designed for determining, depending on the function input quantities made available at the first interface and a specified multitude of rules, the one output quantity or the output quantities which characterize an operating strategy from a multitude of specified operating strategies, and make available the output quantities at the second interface.
The run-time environment is a software program which is implemented together with an application program which cannot communicate directly with an operating system. The run-time environment has the effect that the application program can be implemented on a respective processor platform in that it mediates between the application program and the operating system.
In this case, the processor platform is the totality of the hardware used for the program implementation, particularly the actual microprocessor and/or microcontroller as well as volatile and non-volatile memories which are used for storing data during a program implementation. The secured run-time environment permits a protected implementation of programs. In this case, the programs are shielded from an additional system such that the implementation of the programs has no undesirable effect on the additional system. The secured run-time environment is also called a sandbox. A formation of the function module in the secured run-time environment makes it possible that the program code of the function module ca be implemented in a manner shielded from the basic module, so that the implementation of the program code of the function module has no undesirable effects on basic module, for example, in the form of a memory corruption and/or of faulty jump instructions. This also makes it possible that the program code of the function module can be changed independently of the basic module. The formation of the function module in the secured run-time environment can also make it possible that the program code for the function module can be transmitted to the control unit independently of a program code of the basic module by an appropriately designed programming device.
The respective operating quantity may comprise a measured quantity or a state quantity or a further quantity derived from measured quantities and/or state quantities. The respective operating quantity may characterize an operating state, a driving state and/or environmental state. The determination of the at least one function input quantity preferably takes place such that the at least one function input quantity characterizes a system behavior of the motor vehicle independently of a current sensor configuration. Such an abstraction of the at least one function input quantity advantageously makes it possible that, in the case of a change of the sensor configuration, only the determination of the at least one function input quantity has to be changed, but not the operating strategy and/or the multitude of rules. Analogously, the at least one output quantity characterizes a desired system behavior, which can be implemented by way of the actuators. The at least one output quantity is therefore preferably independent of an actuator configuration.
The determination of the output quantities which each characterize an operating strategy, depending on the multitude of specified rules, makes it possible to indicate an abstract function model of the motor vehicle in a simple manner independently of a sensor and/or actuator configuration. This can contribute to simplifying and improving a serviceability of at least a part of the control system and/or automatic control system of the vehicle. In addition, it becomes possible that the operating strategies can easily be adapted, improved and/or further operating strategies can very easily be added. This can, in turn, contribute to reducing a fault probability in the development of the function model, to lowering development costs and/or to increasing a reliability of the motor vehicle. Furthermore, this can contribute to reducing a complexity of the control system and/or automatic control system of the motor vehicle and/or, while the complexity remains the same, to expanding a functionality of the control system and/or automatic control system of the motor vehicle.
By way of the operating strategy, preferably the provision type of the required energy is specified and/or a maximally allotted energy fraction of the provided energy is in each case specified for users. For the motor vehicle, operating strategies can be specified which can be assigned to different hierarchical levels of the energy distribution in the motor vehicle. The operating strategy may concern individual components of the motor vehicle, for example, a component for converting energy, such as a generator. In addition, the operating strategy may relate to a unit having several components of the motor vehicle, for example, to a low-voltage onboard power supply system of the motor vehicle. The operating strategy may further relate to a partial system of the motor vehicle, which comprises several units, such as an overall onboard power supply system of the motor vehicle, which comprises the low-voltage onboard power supply system and a high-voltage onboard power supply system. A first operating strategy may, for example, be that a hybrid drive device of a hybrid drive vehicle is operated purely electrically. A second operating strategy may, for example, be that the hybrid drive device is operated only by the internal-combustion engine. A third operating strategy may, for example, be that the hybrid drive device is operated in a mixed operation. A fourth operating strategy may, for example, be that the motor vehicle is operated in a recuperation operation.
In an advantageous further development, the function module is designed for determining the at least one function input quantity depending on a specified aggregation function. In this case, specified operating quantities can be assigned to a specific group and, depending on the aggregation function, generalized information can be determined concerning the entire group. One example of the above is a determination of an average value. For example, an average charging state can be determined depending on a respective charging state of energy accumulators in the motor vehicle. Advantageously, the determination of the function input quantities can therefore take place in a very simple manner. In addition, it also becomes possible to relate quantities determined in this manner simply to specified reference quantities in order to obtain a suitable decoupling of the function input quantities flora the sensor configuration of the motor vehicle.
In a further advantageous development, the multitude of rules has rules comprising conditional instructions. Colloquially, such rules are also called “if-then” conditions. This permits the describing of the function model by use of a small multitude of simple language elements and/or syntax. As a result, the function model may be simpler and more comprehensible, whereby an adaptation and/or a fault finding can be carried out significantly more easily.
In a further advantageous development, the secured run-time environment comprises a virtual machine.
In a further advantageous development, the secured run-time environment is designed for implementing bytecode. The bytecode comprises a specified multitude of commands for a virtual machine. When compiling a source text of some programming languages or environments, such as Java, a machine code is not established directly, but rather an intermediate code, bytecode, is established. This code is preferably independent of a real hardware platform and is often relatively compact in comparison to the source code.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawing.